With remarkable growth of computer, electronic, and communication technologies, a great variety of wireless communication services using a wireless network have been developed and introduced. Thus, services offered by a mobile communication system using a wireless network are now making progress toward a multimedia communication service capable of transmitting circuit data, packet data, etc. as well as a traditional voice service.
Among various wireless Internet services using mobile communication terminals, LBS (Location Based Service) is recently drawing much attention in view of wide usability and convenience. LBS refers to a kind of communication service that finds the location of a mobile communication terminal such as a mobile phone, a PDA (Personal Digital Assistant), or the like, and provides additional information associated with the found location. Location positioning techniques used for LBS are normally classified into a network based type for finding the location in a software manner by using propagation environments (i.e., the cell radius of a base station in a mobile communication network), a handset based type using a GPS (Global Positioning System) receiver embedded in a mobile communication terminal, and a hybrid type of both types.
From among these types, the location positioning technique of network based type is being widely used in a GPS shadow zone. This technique, however, has a drawback that location positioning performance may be lowered due to repeater environments or the like. Additionally, less dense distribution of base stations themselves may often cause an inaccurate location positioning.